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Discussion Starter #1
What could cause excessive exhaust back pressure? I've gone through 3 ebp sensors in the past 6 months and finally was able to hook a computer up to my truck the other day and noticed that my actual ebp was much higher than my desired.
 

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Clogged cat converter?
 

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I didn't think it was possible to have too much back pressure when you have a 4" turbo back straight pipe. :dunno: Maybe a stray cat climbed up into your exhaust? :doh:
 

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Discussion Starter #4
Clogged cat converter?
Straight pipe all the way through. The only thing I can think of so far would be the vgt actuator is not opening up the vanes enough. The delta between my ebp actual and ebp desired is the farthest apart at idle. I do think I have a slight exhaust leak on the driver side manifold but I don't see how that would cause excessive back pressure.
 

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just for curiosity has this issue just popped up instantly or has it grown little bit in time?

is it possible that your desired and measured values are off cause of mods of your truck?

if i understand right, you have little improved your fuel and air delivery to your cylinders...

i can be way off with this but just a thought..

what kind of EGT temps you have in general?
 

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Discussion Starter #6
just for curiosity has this issue just popped up instantly or has it grown little bit in time?

is it possible that your desired and measured values are off cause of mods of your truck?

if i understand right, you have little improved your fuel and air delivery to your cylinders...

i can be way off with this but just a thought..

what kind of EGT temps you have in general?
The issue came about around early April. I think it's possible they could be slightly off from the mods. But they're not slightly off, they're way off. They rise and fall proportionally though. WOT I can hit 1600 degrees easy but just driving around they are not much different than stock. Cruising at 75-80 on the highway they will stay between 600-750.
 

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might be sticking vanes or not right working vgt...

can restriction on charged air side like cooler or something cause brakeing to turbo?
or is it even possible?

what kind of map or boost readings you have?

have you try to return stock and back?
or vgt re learn?
 

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Discussion Starter #8
might be sticking vanes or not right working vgt...

can restriction on charged air side like cooler or something cause brakeing to turbo?
or is it even possible?

what kind of map or boost readings you have?

have you try to return stock and back?
or vgt re learn?
Haven't monitored map. There a few things I'm going to check out when I get some spare time. I don't think anything is wrong with the turbo because I don't have any problems when I have a working ebp sensor. I know the sensor is shot because its throwing an ebp circuit A code. It's the same code that I have had ever time. Not sure if you have ever looked at one up close but on the side that goes into the tube that connects to the manifold, there is a white screen looking thing. Whenever they go bad, from my experience at least, there's so much back pressure that it pushes the screen up into the sensor or something along those lines because it's gone when I swap the sensors out. I guess over time the excess pressure weakens it.
 

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Did you check the wire harness
 

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Haven't monitored map. There a few things I'm going to check out when I get some spare time. I don't think anything is wrong with the turbo because I don't have any problems when I have a working ebp sensor. I know the sensor is shot because its throwing an ebp circuit A code. It's the same code that I have had ever time. Not sure if you have ever looked at one up close but on the side that goes into the tube that connects to the manifold, there is a white screen looking thing. Whenever they go bad, from my experience at least, there's so much back pressure that it pushes the screen up into the sensor or something along those lines because it's gone when I swap the sensors out. I guess over time the excess pressure weakens it.
i have -03 model so i belive i have a different sensor or atleast it is located different place, when i did HG's job to my truck i did clean the sensor and it was near complete clogged and the adapter plus the line was glogged as well. didn't see any screen what i can remember.

but i haven't had any problems with the sensor ....yet.
 

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What EBP actual pressures are you seeing? With my PowerMax, I have seen 50-51psi. To me, it sounds like your VGT solenoid may be acting up and you might want to check the wiring to the solenoid itself. It could also be sticking vanes, which would tend to spike the EBP until the vanes free up.
 

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Discussion Starter #12
What EBP actual pressures are you seeing? With my PowerMax, I have seen 50-51psi. To me, it sounds like your VGT solenoid may be acting up and you might want to check the wiring to the solenoid itself. It could also be sticking vanes, which would tend to spike the EBP until the vanes free up.
I can't remember exactly I'll have to monitor it again. I wanna say like 60+.
 
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